Sheet feeding mechanism



` s sheets-sheet 1 INVENTOR ATT() EY W. H.` AYRES Filed May 4, 1940 SVMy@ 3 SHEET FEEDING MEGHANISM K Tf su Feb. 24, 1942.

Febo 24, W' H-AYRES SHEET FEEDING MECHANISM l Filed May 4, 1940 5Sheets-Sheet4 2 INVENTOR 2;, l BY 41 A0.

Feb. 24, 1942.

w. H. AYREs SHEET FEEDING MECHANISM Filed May 4, 1940 3 Sheets-Sheet 3INVENTR wm.N 7V. BY LA.. l0.

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v AT1-on EY l Patented Feb. 24, 1942 osi-reo str-s s l rarest l orticaWilliam`H.,Ayres, Baltimore, Md., assigner to American Can Company, NewYork, N. Y., av corporation of 'New Jersey Application May4, 1940,SerialNo.33.3295` 1i Claims.

There are sometimes two of these feedv 'anA vbars in spaced vandparallel relation extending longitudinally of the machine and eachv bar`is provided with feed dog-s which are transversely parallel. A sheetupon entering the region of the feed bars sometimes has its rear orfeeding edge out of parallel with the first set of feed dogs and usuallythe engagement of the feed dogs with the sheetl brings this edge intokparallelism with them. 'At high speeds it has been found that suchaligning of the sheet by a rsingle dog striking against the sheet edgedents it to such an extent that considerable trouble is caused insubsequent operations upon the sheet or partsr thereof.

The instant invention contemplates overcoming this difculty by the useof a device'which aligns the sheet prior to its engagement by the feeddogs so that when the feed dogs pick it up for further advancement theforce of impact is" Another object is the provision of such a feedi ingmechanism which permits of considerably greater feeding speeds so thatthe sheets may be propelled through the machine at highspeed withoutdamage to the sheet edges.

Numerous other objects and advantages of the invention will be apparentas it isbetter understood from the `following description,` which,

taken in connection with the accompanying drawings, discloses apreferred embodiment I thereof. y

Referring to the drawings: Figure 1 is a top plan View of a portion of ascroll'shear machine embodying the instant invention, with parts brokenaway;

Fig. 2 is a longitudinal section taliensubstantially along the line 2-2in Fig. 1, with parts broken away, 'the section `also showing a sheetentering the machine; w

Fig. 3 is an enlarged longitudinal section taken substantially along theline 3-3 in Fig. 1 and showing a sheet being fed, with parts brokenaway; v

Fig. 4 is an enlargedtransverse section taken substantially along theline lt--A in Fig. 1, with parts broken away;

Fig. 5 is an enlarged detail of the feeding del' vice as viewedsubstantially along the line 5-5 in Fig. 1, with parts broken away; and

Fig. 6 is an end elevation of the detail shown in Fig. 5, with partsbroken away and parts shown in section..

As a preferred embodiment of the instant invention the drawingsillustrate principal parts` of the sheet feed-in portion of a scrollshear` machine of the character disclosed in United States Patent1,846,330, issued February 23, 1932,r

to M. L. I-Ieald. In sucha machine metallic sheets A to be operated uponare fed along a horizontal table Il (Figs. 1, 2, 3, and 4) in Ianintermittent or step-by-step motion so that a plurality of scroll edgedstrips will be cut from each sheet. This step-by-step motion ispreferablyeffected bya pair of spaced and parallel feed bars l2 whichoperate in grooves I3 formed in the top of the table and which extendlongitudinallyI of the machine. Gibs lil secured in the table overlapthe feed bars and thus retain them against displacement.

Each feed bar l2 is provided with a plurality of spring held depressiblefeed dogs I6 which are spaced at equal intervals along the length of thebar. These dogs are' mounted on pivot pins Il which are securedin thefeed bars. ITransversely of the table Il the feed dogs iii in the feedbars are arranged in parallelism so that a sheet delivered'onto thetable in front of the dogs will be carriedforward in a squared position.For this purpose the feed bars are preferably tied together and arereciprocated in unison on a forward feeding stroke and then onareturnstroke in any suitable manner operating` in time with the other movableparts of the machine.

Delivery of a sheet A onto the table il in a proper position relativetothe first set of feed dogs I6 is preferably brought about by a feedingdevice which is connected-to the feed-in end oi" the table. This feedingdevice includes a feed table 2| which forms an extension of the machinetable The feed table 2| comprises a plurality of spaced and parallelflat bars 22 which extend longitudinally of the machine. At one end ofthe table these bars are tied together by a round cross bar 23 whichextends through brackets 24 bolted to the bottom of the bars. The twooutside table bars 22 are formed with outwardly flared side guides 26which guide the sheet in a straight line along the table. At the innerend of the table the bars 22 between the outer bars are tied togetherIby a fiat cross bar 2l.

Adjacent the machine table the feed table 2| is supported on a rotatingcross shaft 3l which is journaled in bearing brackets 32 secured to theouter end of the table Brackets 33 which are secured to the outer tablebars 22 and to two of the intermediate table bars 22, surround the shaftand thus support this end of the feed table. The outer end of the feedtable is supported on upright legs 34.

A sheet A placed upon the feed table 2| is propelled therealong towardthe machine table Il by an endless chain conveyor 36 having a pluralityof spaced feed fingers 3l secured thereto. This conveyor is disposed inthe middle of the table and takes over a driving sprocket 38 which issecured to the cross shaft 3| and over an idler sprocket 39 which iskeyed to a rotatable cross shaft 4| carried in bearing brackets 42secured to the bottoms of the two outer table bars 22.

The driving sprocket 38 and its cross shaft 3| is rotated by an endlesschain 45 which takes over a sprocket 46 mounted on the shaft 3| adjacentthe sprocket 38 and over a sprocket 4l carried on a shaft 48 journaledin suitable bearings formed in the machine table The sprocket Y47 andthe chain d5 are disposed in an opening 49 formed in the machine table.Shaft 48 constitutes the main machine drive shaft and is rotated in time'with the other moving parts of the machine by Way of a driving Achain52 which takes over a sprocket 53 carried on the shaft.

In order to properly advance a sheet when engaged by the feed dogs I6 sothat all of the operations may be performed on the sheet and the sheetremoved from the machine table the feed bars l2 may be reciprocated backand forth so that the actual lineal travel forward of the feed dogs I6when in engagement with the sheet may be ve times as fast as the linealtravel of a feed finger 31 when engaged with the next succeeding sheet.

The sheet A propelled along the yfeed table 2| by the conveyor 36 iscarried up onto the machine table by the conveyor fingers 37 and just asthe rear edge of the sheet comes adjacent the inner conveyor sprocket 38this edge of the sheet is squared up or brought into parallelism withthe first set of dogs I6 of the feed bars |2 which are at this time in arear-most position ready to engage the sheet and carry it forwardthrough the machine.

squaring of the sheet in this manner is brought about by a pair ofsquaring devices 6| (Figs. 1, 5 and 6) which are carried .on therotating cross shaft 3|. There is one of these squaring devices locatedon each side of the feed table 2| in the path of travel of the sheet.

Each squaring device 6| includes .a disc 62 having a hub 63 which ispinned onto the rotating shaft,3|. On its inner face the disc carries anarm 65 having at its outer end a sheet squaring finger 66 formedpreferably with a straight squaring surface 61. At its opposite or innerend the arm is mounted on a pivot stud 68 secured in the disc. Thispivoted end of the arm is formed with a boss 1| which engages against aspring barrel 12 retained in a lug 'I3 formed on the disc. A compressionspring 'I4 disposed in the spring barrel presses the latter outwardlyagainst the arm.

Intermediate its length the squaring arm 65 carries a cam roller 16which operates on an edge cam 11. The spring barrel 12 maintains the camroller in engagement with this cam. The cam is formed integrally with aplate 'I8 which is disposed on the cross shaft 3| but is free to rotatethereon, a collar 'I9 secured to the shaft being provided to preventendwise displacement of the cam and its plate relative to the disc 62.

The cam 'Il and its plate 'I8 are positively rotated on the cross shaft3| in a predetermined timed order relative to the other moving parts ofthe machine. This is brought about by an endless chain 8| which takesover a sprocket 82 bolted to the outer face of the plate 'i8 and over adriving sprocket B3 which is secured to the rotating cross shaft 4|.There is one of these chains @land its sprockets 82, 83 for eachsquaring device 6|.

Sprockets 82, 83 rotate the cam 'VI at a speed one half as fast as thesquaring finger disc 62. In other words the cross shaft 3| whichoperates the sheet conveyor 36 makes two revolutions for each sheetdelivered from the feed table 2| While the cam 'H makes only onerevolution for each sheet. Thus the independently driven disc and camconstitute a differential mechanism in which the disc rotates fasterthan the cam.

The normal position of the squaring finger 66 as it is carried aroundwith the disc is below or within the periphery of the disc where it isout of engagement with a sheet A passing over the squaring device. Whilein this position the cam roller 16 traverses a low part of the rotatingcam. However, once for every two revolutions of the disc the cam rollercatches up with a high portion of the cam and the squaring nger 66 isforced outwardly beyond the periphery of the disc.

The outward shifting of the squaring fingers 66 is effected in time withthe travel of the sheet conveyor fingers 3l. This timing is such as tobring the squaring fingers up behind the rear edge of the sheet just atthe critical moment when the conveyor fingers 3l are delivering thesheet A from the feed table 2| onto the machine table Il where the feeddogs I6 are waiting to engage the sheet.

The motion of the squaring ngers 66 is the resultant of two componentmotions, i. e., the ro tation of the disc 62 and the movement producedby the arcing which takes place when the cam H shifts the fingeroutwardly. These two motions impart to the squaring finger a resultantspeed which slightly exceeds that of the conveyor finger 3l at the pointof transfer from the feed table 2| to the machine table il. The faces 6lof the squaring fingers therefore engage the rear edge of the sheet andtake it away from the conveyor finger 3l the While squaring the sheetinto proper position. When the rear edge of the sheet is against theface 61 of both squaring'fingers 66 it is in a squared and properposition. Y

The feed bars I 2y of the machine proper are also actuated in time withthe operation of the squaring devices 6I just explained and hence theduly squared sheet is immediately picked up, while still in motion withthe squaring finger still in engagement withthe rear edge of the sheetand while still squared asy shown in Fig. 3, by the feed bars as theyoperate through aforward stroke. This carries the sheet through themachine.

As the feed bars I2 advance the sheetA throughl its first steppedvmovement the rear edge of the vwith its rear edge in parallelism withthe feed dogs I6 of the machine feed bars I2, the impact of engagementof the feed dogs with the sheet edge is gentle and isequally distributedbetween the dogs and denting of the sheet edge by this impact is therebyprevented. With such a feeding device `high feeding speeds are readilyobi ing the sheet along a predetermined path of travel,instrumentalities for conveying said sheetsand for delivering them ontosaid feeding means, and rotary devices between said feeding means andsaid instrumentalities for aligning said sheet edge with said feed dogsprior to engagement by them, said rotary devices also maintaining saidaligned sheet in motion while the feed dogs kengage the feeding edge ofthe sheet so that the impact of engagement of the dogs with the sheetedge will be gentle and evenly distributed between them to preventdenting of the sheet edge.

3. A sheet feeding mechanism, comprising, in combination a plurality ofreciprocating feedl bars having feed dogs secured thereto for engagingthe rear edge of a sheet for advancing the sheet along a predeterminedpath of travel, an endless chain conveyorhaving feed ngers fordelivering a sheet the foregoing description, and it will be apparentthat Various changes may be made in the form, construction andarrangement of the parts Without departing from the spirit and' scope ofthe invention or sacrificing all of its material adedge with said feeddogs prior to engagement by them so that thev impact of engagement ofthe dogs with the sheet edge will be evenly distributed between them toprevent denting of thel sheet edge. e

2. A sheet feeding mechanism,.comprising in combination feeding meansincluding feed dogs for engaging the rear edge of a sheet for advancontosaid feed bars, and a plurality of sheet squaring fingers operable intime with the delivery of said y sheet onto said feed bars andengageable against the feeding edge of said sheet for bringing saidsheet edge into parallelism with the dogs on said feed bars and formaintaining the squared sheet in motion while the feed dogs come intofeeding engagement with the sheet edge to prevent denting of the edgeduring this initial feeding engagement.

4. A sheet feeding mechanism, comprising in -combination a plurality ofreciprocating feed bars having feed dogs secured thereto for engagingthe rear edge ofa sheet for advancing the sheet along a predeterminedpath of travel, an endless chain conveyor having feed fingers fordelivering a` sheet onto said feed bars, a pair of spaced rotatablediscs adjacent the path'of travel of the sheet on said conveyor, asquari'ng finger pivotally mounted on each of said discs, a cam adjacenteach of said discs for actuating said sduaring fingers, and means forrotating said cams in a differential relation to the rotation of saiddiscs to give said squaring fingers a component arcuate motion in timewith the delivery of the sheet onto the feed bars for engaging thefeeding edge of the sheet and for bringing it into parallelism with saidfeed dogs prior to its engagement thereby, said squaring fingersaccelerating the sheet to carry it away from said conveyor fingers andmaintaining the sheet in motion while the feed dogs come into feedingengagement therewith to prevent denting of the sheet edge by the dogs.

WILLIAM H. AYRES.

